#![no_std]
#![feature(asm, used, const_fn, naked_functions, alloc, box_syntax)]
#![no_main]
#![feature(extern_prelude)]

#[macro_use]
extern crate hcl;

#[macro_use]
extern crate alloc;

use core::mem;
use hcl::platform::gpio;
use hcl::platform::irq;
use hcl::platform::rcc;
use hcl::platform::scs;
use hcl::platform::timer;
use hcl::platform::usart;
use hcl::platform::dma;
use hcl::dma::*;

mod debug;

use debug::UsartPrinter;

fn configure_clocks(rcc: &mut rcc::RCC) {
    rcc.clock_control.set_hse_on(true);
    while !rcc.clock_control.hse_ready() {
    }

    rcc.clock_config.configure(|c| c
        .set_pll_multiplier(10)
        .set_pll_source(rcc::PllSource::HsiDiv2));

    rcc.clock_control.set_pll_on(true);
    while !rcc.clock_control.pll_ready() {
    }

    rcc.clock_config.switch_clock_source(rcc::SystemClockSource::Pll);
}

fn configure_peripherals(rcc: &mut hcl::platform::rcc::RCC,
                                gpio: &mut gpio::GPIO,
                                usart: &mut usart::USART) {
    rcc.apb2_enable.set_gpio_a(true);
    rcc.apb1_enable.configure(|a| a
        .set_usart2(true));
    rcc.ahb_enable.set_dma1(true);

    gpio.configure(|g| g
        .set_mode(2, gpio::PinMode::Output2MHz)
        .set_output_config(2, gpio::OutputConfig::AfPushPull)
        .set_mode(3, gpio::PinMode::Output50MHz)
        .set_output_config(3, gpio::OutputConfig::AfPushPull)
        .set_mode(5, gpio::PinMode::Output50MHz)
        .set_output_config(5, gpio::OutputConfig::PushPull));

    usart.configure(|u| u
        .set_enabled(true)
        .set_tx_enabled(true)
        .set_dma_transmit_enabled(true)
        .set_baudgen((21, 11))); // 115.2 kbaud
}



// allowing inlining into main() breaks the stack, since main() must be naked to set up a process stack.
#[inline(never)]
fn run(mut scs: scs::Instance, mut p: hcl::platform::Instance) {
    configure_clocks(&mut p.rcc);
    configure_peripherals(&mut p.rcc, &mut p.gpio_a, &mut p.usart2);

    let dma = p.dma1.split();


    let mut dma_control = dma.control;


    let printer = UsartPrinter::init(p.usart2.split(), 7, dma.channel7);

    for i in 0u32..0xffffffff {
        let x = format!("> {}\r\n", i).into_bytes();

        priner.print(x);
    }

}


entry_point!(main);
fn main(scs: scs::Instance, p: hcl::platform::Instance) {
    declare_thread_stack!(stack, 512);

    unsafe {
        hcl::set_process_stack(&stack);
        hcl::use_process_stack(true);
    }

    run(scs, p);
}